Previously there have been many different varieties of convertible steps into platforms for wheelchair lifts which usually comprise a plurality of levers and links in comparatively complicated arrangements. These included, of course, reciprocating motors, such as hydraulic pistons for raising and lowering the platform, separate reciprocating motors, such as hydraulic pistons for converting steps into platforms and vice versa, which pistons are connected directly to parts of the steps or connected to levers and links which are connected to parts of the steps. Furthermore, it is known that such reciprocating motors also may be provided with links for operating barriers and ramps on the front edges of the platforms. All of these known mechanisms involve relatively complicated structures for making them more automatic, which employ many moving parts which require maintenance and are subject to failure. Also many of these prior mechanisms were not provided with automatic safety devices, which could cause them to be dangerous if not properly attended during their operation.